OPT=TS....FREQ....IRC

["C.M.Windsor" <MCDI3CMW ^at^ fs1.ch.umist.ac.uk>]

 I am reposting this due to an error sending a previous version (sorry
 for wasted bandwith)
 I am using G94 to perform TS calculations using the methods
 employed by Kendall Houk et al (Modelling of Diels-Alder TS) where by
 LST was used for the initial guess, OPT=TS for the optimisation to
 TS, FREQ to confirm it is a real TS and then an IRQ search around the
 reaction trajectory.  I would like to know the purpose of the FREQ
 calculation other than to calculate the ZPE and check for presence of
 single -ve eigenvalue (already shown in OPT=TS calculation).
 Am I missing something that I should be checking?
 Thanks in advance.
 Carl
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  From Carl Mark Windsor University of Manchester Institute
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